<I>In Vitro</I> Radiosensitizing Effects of Ultrasmall Gadolinium Based Particles on Tumour Cells

Abstract

Since radiotherapy is widely used in cancer treatment, it is essential to develop strategies which lower the irradiation burden while increasing efficacy and become efficient even in radio resistant tumors. Our new strategy is relying on the development of solid hybrid nanoparticles based on rare-earth such as gadolinium. In this paper, we then evidenced that gadolinium-based particles can be designed to enter efficiently into the human glioblastoma cell line U87 in quantities that can be tuned by modifying the incubation conditions. These sub-5 nm particles consist in a core of gadolinium oxide, a shell of polysiloxane and are functionalized by diethylenetriaminepentaacetic acid (DTPA). Although photoelectric effect is maximal in the [10-100 keV] range, such particles were found to possess efficient in-vitro radiosensitizing properties at an energy of 660 keV by using the "single-cell gel electrophoresis comet assay," an assay that measures the number of DNA damage that occurs during irradiation. Even more interesting, the particles have been evidenced by MTT assays to be also efficient radiosensitizers at an energy of 6 MeV for doses comprised between 2 and 8 Gy. The properties of the gadolinium-based particles give promising opening to a particle-assisted radio-therapy by using irradiation systems already installed in the majority of hospitals.

Improving proton therapy by metal-containing nanoparticles: nanoscale insights

“…GdBNs were synthesized as described elsewhere. 25 The nanoparticles are composed of a polysiloxane core surrounded by gadolinium chelates. GdBNs are functionalized with 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid.…”

Preparation, characterization and X-ray attenuation property of Gd2O3-based nanocomposites

“…Gd 2 O 3 nanoparticles find applications in bioimaging (when tagged with fluorescent dyes) (Dosev et al 2006), in magnetic resonance imaging as contrast agent (Fortin et al 2007; Khan et al 2014) and in drug delivery (Khan et al 2014). They are also used as neutron convertors in imaging plate neutron detector (Bhattacharyya and Agrawal 1995;Gunduz and Uslu 1996;Khan et al 2014), as additives in UO 2 fuel rods (Gunduz and Uslu 1996;Khan et al 2014), in ZrO 2 to enhance its toughness (Bhattacharyya and Agrawal 1995;Chen 1996;Khan et al 2014), as a radiosensitizer (Duc et al 2011;Miladi et al 2015;Mowat et al 2011;Rancoule et al 2016;Rima et al 2013), as a catalyst (Hussein 1994;Perevalov et al 2014) and dopants for laser (Perevalov et al 2014) and colourants (Perevalov et al 2014) for special glasses.…”

Nanodiamonds and nanoparticles as tumor cell radiosensitizers—promising results but an obscure mechanism of action

“…This is shown in Grall et al (15). Similarly, a greater efficiency of cell killing was also correlated with an increased induction of DNA DSB in irradiated cells preincubated with some kinds of metal nanoparticles (i.e., nanoparticles composed of high-Z atoms) (20)(21)(22).…”